Document Classes ⇒ beamer | "Frankfurt" Theme

[Houlala]

Hi all,

I want to customize the Frankfurt theme to display only the current section with the subsection circles in the headline. I've searched and it appears that it's a bit tricky to achieve that.

The problem is closer to this post but I want to have the subsection circles (generated with \insertnavigation + \dohead commands).

Any suggestion?
Regards.